How do you know you have the crimp right?
Can a crimp be to tight and drive up pressures unsafely?
Do you just look at the crimp and call it good to go or is there a actual scientific process?
will be Loading +P type ammo in a 45LC Ruger revolver,,,if the crimp is not sufficent,,,will the bullets start backing out after only the first or second shot or can this occur anytime while fireing a cyclinder full?
I have no experiance with this crimp not holding the bullet correctly senerio...but want to learn...

No scientific process, you can usually just tell when its right, sometimes if youre not careful you can overcrimp the case a bit, but then youll start getting a little bulge at the top, then you know you went too far. I hope you have a Redding profile crimp for that 45LC. I could show you a pic but Im not able to post pics here, I use the profile crimp for my 44.

1. The crimp is right if bullets don't move under recoil. Fill a cylinder, shoot and then check cartridges to see if the bullets have moved. If you can shoot 5 cartridges and number 6 still has the bullet in place, you're OK.

2. Crimps add a little but not a lot of pressure.

3. For the 45 Colt, you can probably get by with the crimp given by your bullet seating die though you might want to crimp in a separate operation. That said, I prefer the Lee Factory Crimp Die for crimping.

Neck tension is what mostly keeps the bullets from jumping crimp, moving out of the case on firing. The crimp does help. If the sizing die is working correctly,along with an expander that is smaller then bullet diameter by at least .002", neck tension will be fine. Tho i have seen expanders for larger handguns be .004" under bullet diameters. When you seat a bullet, has it expanded the brass by at least .002" ?

I shot the rounds today,with my hottest load... a 1 grain under recommended max,i had one bullet that rode around unfired in the cyclinder for 12 shots...the bullet had backed out from the very front of the crimp cannalure to the very rear,which is the thichness of the entire cannalure...is this acceptable?
I have the mouth belled as little as possible and the crimp looks fine and dandy..,would you put just a smidge more crimp on this reloaded cartridge or call it good to go?

Usa a Lee Factory crimper or a taper crimper...polish the expander button or the expander section down about 0.001", use a Lyman M die...

A roll crimp can actually cause expansion of the mouth section a bit and a roll crimp DOESN'T guarantee a good grip...I've had bullets in factory crimped AND my own mis-crimped cases actuall spin around by finger grip but they DIDN'T move by recoil.

I like the Lee factory crimper and use it with several straight walled cartridges...I also use a taper crimper for my 45 Auto and 9mm Luger.

Just takes time to work out all the kinks.

LUCK

quote:

Originally posted by blackbearhunter:
I shot the rounds today,with my hottest load... a 1 grain under recommended max,i had one bullet that rode around unfired in the cyclinder for 12 shots...the bullet had backed out from the very front of the crimp cannalure to the very rear,which is the thichness of the entire cannalure...is this acceptable?
I have the mouth belled as little as possible and the crimp looks fine and dandy..,would you put just a smidge more crimp on this reloaded cartridge or call it good to go?

If you want the best crimp possible, get the Redding profile crimp die, none better if you're shooting big, hot magnum loads.
http://shootersforum.com/showthread.htm?t=10030

To give you an idea of how well they work, Im shooting a 330grain Penn Bullets hardcast(SSK type) over 22grs 296, vel. 1400fps, recoil, a shitload. Ive never had a bullet pull out yet.